Abstract: A honeycomb structure includes a first end face, a second end face, and at least one honeycomb unit. The second end face is disposed opposite the first end face along a longitudinal direction of the honeycomb structure. The at least one honeycomb unit has plural cell walls extending along the longitudinal direction from the first end face toward the second end face to define plural cells. The at least one honeycomb unit includes about 50 mass % to about 60 mass % of zeolite, about 15 mass % to about 25 mass % of inorganic fibers, about 20 mass % to about 32 mass % of alumina that is not contained in the zeolite or the inorganic fibers, and an opening ratio Y(%). The opening ratio Y(%) satisfies an expression about 57?Y?0.7X+25, where X (mass %) is a zeolite content of the at least one honeycomb unit.

Abstract: A honeycomb structure includes a honeycomb unit and a coating layer. The honeycomb unit includes inorganic particles, an inorganic binder, and partition walls. The partition walls extend along a longitudinal direction of the honeycomb unit to define plural through holes. The coating layer defines a periphery of the honeycomb structure. A ratio of a specific heat capacity of the coating layer to a specific heat capacity of the honeycomb unit is about 1.0 or less.

Abstract: A honeycomb structure includes at least one honeycomb unit. The at least one honeycomb unit has a longitudinal direction and includes zeolite and an inorganic binder. A content of the zeolite per apparent unit volume of the at least one honeycomb unit is about 230 g/L or greater. The at least one honeycomb includes plural cell walls extending from one end face to another end face along the longitudinal direction to define plural cell walls. A porosity of substantially all pores in the cell walls is about 40% or less. A porosity of pores having diameters in a range of about 0.005 ?m through about 0.02 ?m in the cell walls is about 5% or greater. A porosity of pores having diameters in a range of about 0.05 ?m through about 0.2 ?m in the cell walls is about 17.5% or greater.

Abstract: A honeycomb structure includes a honeycomb unit which has zeolite, inorganic binder, and cell walls extending from one end to another end along a longitudinal direction of the honeycomb unit to define cells. An amount of zeolite contained per apparent unit volume of the honeycomb unit is approximately 230 g/L or more. Mathematical formulae [1] and [2] are satisfied when a thickness of the cell walls is defined as X mm and an average pore diameter of a surface of the cell walls observed by a microscope is defined as Y ?m: X+0.07?Y?X+0.27 ??[1] approximately 0.15?X?approximately 0.35 ??[2].

Abstract: A honeycomb structure includes at least one honeycomb unit. The at least one honeycomb unit has a longitudinal direction and includes plural cell walls extending from one end face to another end face along the longitudinal direction to define plural cells. The at least one honeycomb unit includes inorganic particles, an inorganic binder, and inorganic fibers. A degree of orientation of the inorganic fibers in an a-axis direction parallel to the longitudinal direction is about 0.5 or less.

Abstract: A honeycomb structure includes a plurality of honeycomb units and an adhesive layer. Each of the plurality of honeycomb units has a longitudinal direction and includes zeolite, an inorganic binder, a first end face, a second end face, and a cell wall. The second end face is located opposite to the first end face in the longitudinal direction. The cell wall extends from the first end face to the second end face along the longitudinal direction to define cells. The adhesive layer includes zeolite and is provided between the plurality of honeycomb units to connect the plurality of honeycomb units. A ratio of a coefficient of thermal expansion of the adhesive layer to a coefficient of thermal expansion of each of the plurality of honeycomb units is in a range from approximately 0.8 to approximately 1.2.

Abstract: A honeycomb structure includes at least one honeycomb unit. The at least one honeycomb unit has a longitudinal direction and cell walls extending from one end face to another end face along the longitudinal direction to define cells. The at least one honeycomb unit includes an inorganic binder, and zeolite ion-exchanged with plural kinds of metal ions.

Abstract: A honeycomb structure includes a honeycomb unit having inorganic particles, an inorganic binder and inorganic fibers. A value of (D90-D10)/D50, which indicates a length distribution of the inorganic fibers, is about two or less, where, when the fiber length is taken in a horizontal axis and a volume frequency is taken in a vertical axis, D10 is a fiber length at 10% by volume, D50 is a fiber length at 50% by volume, and D90 is a fiber length at 90% by volume, where D10<D50<D90.

Abstract: A honeycomb structure includes a honeycomb unit containing zeolite and an inorganic binder and having cell walls extending from one end to another end along a longitudinal direction of the honeycomb unit to define cells. An amount of zeolite contained per apparent unit volume of the honeycomb unit is approximately 230 g/L or more. A thickness X mm of the cell walls is in a range from approximately 0.15 mm to approximately 0.35 mm. A mathematical formula 40X+20?Y?40X+30 is satisfied when a porosity of the cell walls is defined as Y %.

Abstract: A honeycomb structure includes a center area, an outer peripheral area, and at least one honeycomb unit having a longitudinal direction. The center area has a smaller similarity shape in relation to a peripheral shape of the honeycomb structure in a cross section perpendicular to the longitudinal direction. The smaller similarity shape is defined by including a center of the honeycomb structure and substantially a half of a length from the center to the peripheral shape of the honeycomb structure. The outer peripheral area is located outside the smaller similarity shape. An aperture ratio of the honeycomb structure is from approximately 50% to approximately 65% in the cross section of the honeycomb structure. The aperture ratio includes a first aperture ratio in the outer peripheral area and a second aperture ratio in the center area. The first aperture ratio is larger than the second aperture ratio.

Abstract: A honeycomb structure includes a honeycomb structure includes a honeycomb unit. The honeycomb unit has thermal conductivity equal to or greater than about 0.15 W/m/K but less than or equal to about 0.60 W/m/K and has Young's modulus equal to or greater than about 1.5 MPa but less than or equal to about 7.0 Mpa. The honeycomb unit includes zeolite, an inorganic binder, and partition walls. The partition walls extend along a longitudinal direction of the honeycomb unit to define plural through holes.

Abstract: A honeycomb structure includes at least one honeycomb unit and a peripheral wall at a peripheral surface connecting one end face and another end face of the honeycomb structure. The honeycomb unit includes inorganic particles, an inorganic binder, and cell walls extending along a longitudinal direction of the at least one honeycomb unit to define cells. The at least one honeycomb unit has a b-axis compression strength of about 1.0 MPa or less. A thickness T of the peripheral wall of the honeycomb structure is larger than 0.42V-0.25 (mm), where V is a volume of the honeycomb structure and in a range from about 1.0 liters to about 10 liters.

Abstract: A honeycomb structure includes at least one honeycomb unit. The at least one honeycomb unit includes zeolite, inorganic binder, and cell walls extending from a first end face to a second end face along a longitudinal direction of the at least one honeycomb unit to define cells. The at least one honeycomb unit includes a cross-sectional surface orthogonal to the longitudinal direction having a substantially square shape. An aperture ratio of the at least one honeycomb unit is in a range from about 50% to about 65%. A formula 12.5V+50<Lc/wc<12.5V+200 is satisfied, where V (liter) denotes the volume of the honeycomb structure and the wc (cm) and Lc (cm) denote a cell width and a total length of the cells, respectively.

Abstract: A honeycomb structure includes honeycomb units. Each of the honeycomb units has a longitudinal direction and includes inorganic particles, an inorganic binder, and cell walls defining cells extending along the longitudinal direction from one end face to another end face. The honeycomb units are bonded together via an adhesive such that each longitudinal direction is substantially in parallel. An amount of ammonia desorbed per unit mass of the honeycomb units is about 5 to about 100 times greater than an amount of ammonia desorbed per unit mass of the adhesive. The amount of ammonia desorbed per unit mass of the honeycomb units and the amount of ammonia desorbed per unit mass of the adhesive are measured by an NH3-TPD method.

Abstract: A honeycomb structure includes an inorganic particle, inorganic binder, a honeycomb unit, a first end face, and a second end face. The honeycomb unit includes plural partition walls extending along a longitudinal direction of the honeycomb unit to define through-holes. The first end face is substantially perpendicular to the longitudinal direction and provided at a first end of the honeycomb structure. The second end face is substantially perpendicular to the longitudinal direction and provided at a second end opposite to the first end in the longitudinal direction of the honeycomb structure. First circularity of the first end face and second circularity of the second end face are about 1.5 mm to about 4.0 mm. The circularity of the first end face is different from the circularity of the second end face.

Abstract: A honeycomb structure includes at least one honeycomb unit which includes walls. The walls have a thickness of from about 0.10 mm to about 0.50 mm and extend along a longitudinal direction of the honeycomb structure to define through-holes. The honeycomb structure has a center area inside a boundary line passing through positions located at substantially a half of a length from a center of the honeycomb structure to a periphery of the honeycomb structure in a cross section perpendicular to the longitudinal direction. The honeycomb structure has a peripheral area outside the boundary line. A thickness of the walls located in the peripheral area is larger than a thickness of the walls located in the center area. A first opening ratio in the center area in the cross section is larger than a second opening ratio in the peripheral area in the cross section.

Abstract: A honeycomb structure includes at least one honeycomb unit having a longitudinal direction and including cell walls extending along the longitudinal direction from one end face to another end face to define cells. The at least one honeycomb unit includes inorganic particles, inorganic binder, and inorganic fibers. The inorganic fibers include a bio-soluble inorganic compound.

Abstract: A honeycomb structure includes at least one honeycomb unit a NOx occluding catalyst and a noble metal catalyst. The at least one honeycomb unit includes inorganic particles and an inorganic binder and has a plurality of cell walls extending from one end face to another end face of the at least one honeycomb unit along a longitudinal direction of the at least one honeycomb unit to define a plurality of cells. The NOx occluding catalyst and the noble metal catalyst are provided at the plurality of cell walls. An amount of the noble metal catalyst provided on a surface of at least one of the plurality of cell walls is greater than an amount of the noble metal catalyst provided in a center part along a thickness of the at least one of the plurality of cell walls.

Abstract: A honeycomb structure includes at least one honeycomb unit having a longitudinal direction. The honeycomb unit includes SOx storage agent, inorganic particles, inorganic binder, and a partition wall extending along the longitudinal direction to define plural through holes. An expression Y??26X+40000 (0<X?approximately 500) is satisfied, wherein “X” represents an amount [g] of SOx stored in the honeycomb structure, and “Y” represents a specific surface area [m2/L] of the honeycomb structure when “X” [g] of SOx is stored in the honeycomb structure.

Abstract: A honeycomb structure includes at least one honeycomb unit and coating layers. The at least one honeycomb unit includes a first SOx-occluding agent, first inorganic particles, an inorganic binder, and partition walls extending along the longitudinal direction of the at least one honeycomb unit to define parallel through holes. The coating layers are formed on the partition walls. A basicity of the at least one honeycomb unit is higher than a basicity of the coating layers. The coating layers include a second SOx-occluding agent and second inorganic particles.